The International
Crocodilian
Genomes
Working Group (ICGWG) is leading a
large-scale effort to use genomic methods to examine
crocodilian biology. We have targeted the American
alligator (Alligator
mississippiensis), saltwater crocodile (Crocodylus
porosus), and gharial (Gavialis gangeticus) for genome
sequencing and have produced preliminary genome
assemblies.

To complement
these efforts we and others have collected (or
are planning to collect) related data that can be used
to enrich our knowledge of crocodilian genomes. These
data include:

Transcriptome data for various tissues

BAC-end sequences for all three taxa (and some
complete BAC sequences)

We expect the combinination of
these data to result in a high quality genome assembly
with rich annotation that will bring these fascinating
reptiles into the genomic era.

Reptiles (class
Reptilia) represent one of the most diverse vertebrate
groups they have largely been excluded from the
genomics revolution. Extant reptiles comprise four
major groups, traditionally assigned the rank of
order:

Crocodylia (crocodiles and alligators; ~30
species)

Sphenodontia (tuataras; 2 species)

Squamata (lizards and snakes; ~7,900 species)

Testudines (turtles; ~300 species).

The reptile clade also includes
class Aves (birds; ~10,000 species), the sister group
of crocodilians. Birds and crocodilians are the extant
members of the Archosauria ("ruling reptiles"), the
clade that also includes the extinct dinosaurs and
pterosaurs. Given the public interest in these
spectacular animals (and their extinct relatives) they
are also ideal for education and efforts that bridge
genomics and organismal biology.

Crocodilians
have long been a part of the human experience, making
appearences in pop culture and providing sources of
prized commodities such as leather and meat. In
fact, crocodilians are a source of trade
worth over $US 500 million worldwide. Some
crocodilians, like the gharial, are critically
endangered and their genome sequence may provide tools
for genetic monitoring. Crocodilians are
also important for human health; their immune systems
may provide antimicrobial agents and they have been
used to monitor the environment for contaminants, such
as endocrine disruptiors.

Although
crocodilians represent important model organisms
for fields as diverse as developmental biology,
osmoregulation, cardiophysiology, sex determination,
and functional morphology. The ICGWG plans to provide
the genomic resources needed to expand our knowledge
of these fascinating organisms. Since
cocodilians are a pivotal lineage in the vertebrate
tree of life this effort will also provide fascinating
information for comparative genomics.

Personnel

Institutions

funding

This work has received
financial support from the US National Science Foundation
(grants MCB-1052500, MCB-0841821, DEB-1020865, and
DUE-0920151), the Institute for Genomics, Biocomputing
and Biotechnology at Mississippi State University, the
National Institute for Basic Biology and Grants-in-Aid for
Scientific Research from the Ministry of Education, Culture,
Sports, Science and Technology of Japan, and the Australian
Rural Industries Research and Development Corporation
(grants PRJ-000549 and RIRDC PRJ-005355).

disclaimer

The opinions, findings,
recommendations, and conclusions expressed here are those of
the web page authors and do not necessarily reflect the
views of the funding agencies.